下列选项中,()属于加速折旧的方法。 ["新旧程度折旧法","平均年限折旧法","定率折旧法","年数合计法"]
病人女性,28岁,每天午后低热3周(38℃左右),咳少量痰液,乏力和纳差,血沉加快,白细胞7.0×109/L,中性粒细胞60%,胸片示右上肺第2肋间有斑片阴影。咯血致死的主要原因是() ["A.严重贫血","休克","窒息","继发感染","肺不张"]
醋氮酰胺主要抑制() ["胆碱酯酶","碳酸酐酶","前列腺素合成酶","二氢叶酸合成酶","DNA螺旋酶"]
先天性髋关节脱位是() ["股骨头和颈部发育正常","髋关节关节囊和韧带紧张","夏天多见","与胎儿体位无关","髋臼先天发育不良和关节囊松弛而引起股骨头脱位"]
毒扁豆碱主要抑制() ["胆碱酯酶","碳酸酐酶","前列腺素合成酶","二氢叶酸合成酶","DNA螺旋酶"]
气动保位阀的作用是什么?